They just don't reply or call back with feedback, why not?

I have been sending e-mails after sending documentation to not pay for certain claims, a lady called back once 2 weeks ago asking I submit new documentation for claims to be rejected by the fund. I have been sending e-mails on 3 occasions without any feedback from Discovery at all. I need to know what is going on please as tests were done for a heart condition and I went to Hospital Fourways Life and took the matter up with Management. I had high blood pressure and they were informed that I have no heart condition at all, I even told them they can confirm that with my Cardiologist which they did not do. So they did tests and x-rays which was unnecessary as they did not do sugar or urine test before I was consulted which to me is a basic first test just to find that I had a kidney infection so the the doctors and hospital can pick up the bill instead of depleting my savings unnecessary.